Thermosets having desirable properties for use as sealants, composite repair, 3D printing material, and other applications, are in high demand. 3D printing applications in particular have attracted attention for their potential as a new manufacturing process that offers remarkable versatility in producing tailored physical objects from the micro- to the macroscale. Modern advances in 3D printing have produced 3D printers for personal home use, rapid prototyping and production of biomedical devices. In its basic form, a 3D-printing apparatus consists of a deposition nozzle/needle that is connected to a reservoir containing the material to be deposited. Accordingly, the material to be deposited should be shear-thinning enough to flow through a general syringe and/or nozzle of a 3D printer. Furthermore, it may be useful in some cases that the physical object printed by the 3D printer be modifiable post-deposition.
Thermosets generally have material networks consisting of irreversible covalent crosslink junctions that do not reform following a mechanical failure. Recent advances in materials sciences have focused on developing rearrangeable networks and crosslink junctions. However, an inherent problem with continuously reversible (supramolecular) systems is that they suffer from creep due to thermal fluctuations of non-covalent linkages, which eventually leads to material failure. The deleterious effects of creep may be mitigated by the introduction of covalent crosslinks.
Furthermore, traditional materials utilized as print media are generally prepared at high temperature, but the liquid monomers used as polymerizable solvents for material synthesis are not stable at high temperature.
Therefore, there is a need in the art for a thermoset material with finely tuned mechanical properties, i.e. behavior under shear loading, favorable melt-processing capabilities, and syntheses of such material to be performed at lower temperatures within a smaller time period.